<HTML>
<BODY BGCOLOR="white">
<PRE>
<FONT color="green">001</FONT>    package metaface.interaction;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import java.util.*;<a name="line.3"></a>
<FONT color="green">004</FONT>    import java.io.*;<a name="line.4"></a>
<FONT color="green">005</FONT>    /**<a name="line.5"></a>
<FONT color="green">006</FONT>     *  This class is an internal representation of a DMTL document. DMTL is defined<a name="line.6"></a>
<FONT color="green">007</FONT>     *  by the following DMTL structure: <a name="line.7"></a>
<FONT color="green">008</FONT>     *  &lt;IMG SRC="../../resources/DMTL_h.jpg"/>&lt;BR/><a name="line.8"></a>
<FONT color="green">009</FONT>     *  &lt;IMG SRC="../../resources/DMTL_a.jpg"/>&lt;BR/><a name="line.9"></a>
<FONT color="green">010</FONT>     *  See the DMTL &lt;A HREF="../../resources/DMTL.dtd">DTD&lt;/a> or and <a name="line.10"></a>
<FONT color="green">011</FONT>     *  &lt;A HREF="../../resources/dmtl_example.xml">example file&lt;/a> .<a name="line.11"></a>
<FONT color="green">012</FONT>     *<a name="line.12"></a>
<FONT color="green">013</FONT>     *@author     Simon Beard <a name="line.13"></a>
<FONT color="green">014</FONT>     *@version    1.0<a name="line.14"></a>
<FONT color="green">015</FONT>     *@see        InteractionManager<a name="line.15"></a>
<FONT color="green">016</FONT>     *@see        State<a name="line.16"></a>
<FONT color="green">017</FONT>     *@see        DefaultTopic<a name="line.17"></a>
<FONT color="green">018</FONT>     *@see        Evaluate<a name="line.18"></a>
<FONT color="green">019</FONT>     *@see        NextState<a name="line.19"></a>
<FONT color="green">020</FONT>     *@see        PreState<a name="line.20"></a>
<FONT color="green">021</FONT>     *@see        Signal<a name="line.21"></a>
<FONT color="green">022</FONT>     *@see        SubTopic<a name="line.22"></a>
<FONT color="green">023</FONT>     */<a name="line.23"></a>
<FONT color="green">024</FONT>    public class KnowledgeBase {<a name="line.24"></a>
<FONT color="green">025</FONT>            private Vector topics;<a name="line.25"></a>
<FONT color="green">026</FONT>            private DefaultTopic defaulttopic;<a name="line.26"></a>
<FONT color="green">027</FONT>            private String filename;<a name="line.27"></a>
<FONT color="green">028</FONT>            private boolean visited;<a name="line.28"></a>
<FONT color="green">029</FONT>    <a name="line.29"></a>
<FONT color="green">030</FONT>    <a name="line.30"></a>
<FONT color="green">031</FONT>            /**<a name="line.31"></a>
<FONT color="green">032</FONT>             *  Constructor for the KnowledgeBase object<a name="line.32"></a>
<FONT color="green">033</FONT>             *<a name="line.33"></a>
<FONT color="green">034</FONT>             *@param  filenamestring  The DMTL file name, without path information, from<a name="line.34"></a>
<FONT color="green">035</FONT>             *      which this knowledge base was constructed<a name="line.35"></a>
<FONT color="green">036</FONT>             */<a name="line.36"></a>
<FONT color="green">037</FONT>            public KnowledgeBase(String filenamestring) {<a name="line.37"></a>
<FONT color="green">038</FONT>                    filename = filenamestring;<a name="line.38"></a>
<FONT color="green">039</FONT>                    topics = new Vector();<a name="line.39"></a>
<FONT color="green">040</FONT>                    visited = false;<a name="line.40"></a>
<FONT color="green">041</FONT>            }<a name="line.41"></a>
<FONT color="green">042</FONT>    <a name="line.42"></a>
<FONT color="green">043</FONT>    <a name="line.43"></a>
<FONT color="green">044</FONT>            /**<a name="line.44"></a>
<FONT color="green">045</FONT>             *  Adds a Topic element to the KnowledgeBase object<a name="line.45"></a>
<FONT color="green">046</FONT>             *<a name="line.46"></a>
<FONT color="green">047</FONT>             *@param  element  The topic element<a name="line.47"></a>
<FONT color="green">048</FONT>             */<a name="line.48"></a>
<FONT color="green">049</FONT>            public void addTopic(Topic element) {<a name="line.49"></a>
<FONT color="green">050</FONT>                    topics.add(element);<a name="line.50"></a>
<FONT color="green">051</FONT>            }<a name="line.51"></a>
<FONT color="green">052</FONT>    <a name="line.52"></a>
<FONT color="green">053</FONT>    <a name="line.53"></a>
<FONT color="green">054</FONT>            /**<a name="line.54"></a>
<FONT color="green">055</FONT>             *  Adds a DefaultTopic element to the KnowledgeBase object<a name="line.55"></a>
<FONT color="green">056</FONT>             *<a name="line.56"></a>
<FONT color="green">057</FONT>             *@param  element  The default topic element<a name="line.57"></a>
<FONT color="green">058</FONT>             */<a name="line.58"></a>
<FONT color="green">059</FONT>            public void addDefaultTopic(DefaultTopic element) {<a name="line.59"></a>
<FONT color="green">060</FONT>                    defaulttopic = element;<a name="line.60"></a>
<FONT color="green">061</FONT>            }<a name="line.61"></a>
<FONT color="green">062</FONT>    <a name="line.62"></a>
<FONT color="green">063</FONT>    <a name="line.63"></a>
<FONT color="green">064</FONT>            /**<a name="line.64"></a>
<FONT color="green">065</FONT>             *  Gets the filename from which the KnowledgeBase object was constructed<a name="line.65"></a>
<FONT color="green">066</FONT>             *<a name="line.66"></a>
<FONT color="green">067</FONT>             *@return    The filename value<a name="line.67"></a>
<FONT color="green">068</FONT>             */<a name="line.68"></a>
<FONT color="green">069</FONT>            public String getFilename() {<a name="line.69"></a>
<FONT color="green">070</FONT>                    return (filename);<a name="line.70"></a>
<FONT color="green">071</FONT>            }<a name="line.71"></a>
<FONT color="green">072</FONT>    <a name="line.72"></a>
<FONT color="green">073</FONT>    <a name="line.73"></a>
<FONT color="green">074</FONT>            /**<a name="line.74"></a>
<FONT color="green">075</FONT>             *  Gets the topics of the knowledge base<a name="line.75"></a>
<FONT color="green">076</FONT>             *<a name="line.76"></a>
<FONT color="green">077</FONT>             *@return    A list of topics<a name="line.77"></a>
<FONT color="green">078</FONT>             */<a name="line.78"></a>
<FONT color="green">079</FONT>            public Vector getTopics() {<a name="line.79"></a>
<FONT color="green">080</FONT>                    return (topics);<a name="line.80"></a>
<FONT color="green">081</FONT>            }<a name="line.81"></a>
<FONT color="green">082</FONT>    <a name="line.82"></a>
<FONT color="green">083</FONT>    <a name="line.83"></a>
<FONT color="green">084</FONT>            /**<a name="line.84"></a>
<FONT color="green">085</FONT>             *  Gets the default topics of the knowledge base<a name="line.85"></a>
<FONT color="green">086</FONT>             *<a name="line.86"></a>
<FONT color="green">087</FONT>             *@return    The default topic<a name="line.87"></a>
<FONT color="green">088</FONT>             */<a name="line.88"></a>
<FONT color="green">089</FONT>            public DefaultTopic getDefaultTopic() {<a name="line.89"></a>
<FONT color="green">090</FONT>                    return (defaulttopic);<a name="line.90"></a>
<FONT color="green">091</FONT>            }<a name="line.91"></a>
<FONT color="green">092</FONT>    <a name="line.92"></a>
<FONT color="green">093</FONT>    <a name="line.93"></a>
<FONT color="green">094</FONT>            /**<a name="line.94"></a>
<FONT color="green">095</FONT>             *  Building that must commence after construction and initialistation<a name="line.95"></a>
<FONT color="green">096</FONT>             */<a name="line.96"></a>
<FONT color="green">097</FONT>            public void build() {<a name="line.97"></a>
<FONT color="green">098</FONT>            }<a name="line.98"></a>
<FONT color="green">099</FONT>    <a name="line.99"></a>
<FONT color="green">100</FONT>    <a name="line.100"></a>
<FONT color="green">101</FONT>            /**<a name="line.101"></a>
<FONT color="green">102</FONT>             *  Resets state variables of the knowledge base<a name="line.102"></a>
<FONT color="green">103</FONT>             */<a name="line.103"></a>
<FONT color="green">104</FONT>            public void reset() {<a name="line.104"></a>
<FONT color="green">105</FONT>                    visited = false;<a name="line.105"></a>
<FONT color="green">106</FONT>            }<a name="line.106"></a>
<FONT color="green">107</FONT>    <a name="line.107"></a>
<FONT color="green">108</FONT>    <a name="line.108"></a>
<FONT color="green">109</FONT>            /**<a name="line.109"></a>
<FONT color="green">110</FONT>             *  Performs matching of the DMTL representation to a user's stimulus (e.g.<a name="line.110"></a>
<FONT color="green">111</FONT>             *  natural language or hypertext)<a name="line.111"></a>
<FONT color="green">112</FONT>             *<a name="line.112"></a>
<FONT color="green">113</FONT>             *@param  ic  The current interaction context<a name="line.113"></a>
<FONT color="green">114</FONT>             *@return     A lest of the best matching states<a name="line.114"></a>
<FONT color="green">115</FONT>             */<a name="line.115"></a>
<FONT color="green">116</FONT>            public BestList matchStimulus(InteractionContext ic) {<a name="line.116"></a>
<FONT color="green">117</FONT>                    int i;<a name="line.117"></a>
<FONT color="green">118</FONT>                    boolean process;<a name="line.118"></a>
<FONT color="green">119</FONT>                    Topic tmptopic;<a name="line.119"></a>
<FONT color="green">120</FONT>                    Stack path;<a name="line.120"></a>
<FONT color="green">121</FONT>                    BestList bestlist;<a name="line.121"></a>
<FONT color="green">122</FONT>    <a name="line.122"></a>
<FONT color="green">123</FONT>                    //Initialisation<a name="line.123"></a>
<FONT color="green">124</FONT>                    bestlist = new BestList();<a name="line.124"></a>
<FONT color="green">125</FONT>                    process = true;<a name="line.125"></a>
<FONT color="green">126</FONT>                    path = new Stack();<a name="line.126"></a>
<FONT color="green">127</FONT>                    path.push(filename);<a name="line.127"></a>
<FONT color="green">128</FONT>    <a name="line.128"></a>
<FONT color="green">129</FONT>                    //If processing entry states, the knowledge base can only be processed if it yielded a response in the previous interation<a name="line.129"></a>
<FONT color="green">130</FONT>                    if ((ic.processingtype == InteractionManager.ENTRY) && (!visited)) {<a name="line.130"></a>
<FONT color="green">131</FONT>                            process = false;<a name="line.131"></a>
<FONT color="green">132</FONT>                    }<a name="line.132"></a>
<FONT color="green">133</FONT>                    if (process) {<a name="line.133"></a>
<FONT color="green">134</FONT>    <a name="line.134"></a>
<FONT color="green">135</FONT>                            //Process each topic<a name="line.135"></a>
<FONT color="green">136</FONT>                            for (i = 0; i &lt; topics.size(); i++) {<a name="line.136"></a>
<FONT color="green">137</FONT>                                    tmptopic = (Topic) topics.elementAt(i);<a name="line.137"></a>
<FONT color="green">138</FONT>                                    bestlist = tmptopic.matchStimulus(ic, path, bestlist);<a name="line.138"></a>
<FONT color="green">139</FONT>                            }<a name="line.139"></a>
<FONT color="green">140</FONT>                    }<a name="line.140"></a>
<FONT color="green">141</FONT>                    path.pop();<a name="line.141"></a>
<FONT color="green">142</FONT>                    return (bestlist);<a name="line.142"></a>
<FONT color="green">143</FONT>            }<a name="line.143"></a>
<FONT color="green">144</FONT>    <a name="line.144"></a>
<FONT color="green">145</FONT>    <a name="line.145"></a>
<FONT color="green">146</FONT>            /**<a name="line.146"></a>
<FONT color="green">147</FONT>             *  Gets a response based on the path<a name="line.147"></a>
<FONT color="green">148</FONT>             *<a name="line.148"></a>
<FONT color="green">149</FONT>             *@param  path  The path to the target response<a name="line.149"></a>
<FONT color="green">150</FONT>             *@return       A response string consisting of either an absolute path and<a name="line.150"></a>
<FONT color="green">151</FONT>             *      filename, or a textual response, or null if no response is found<a name="line.151"></a>
<FONT color="green">152</FONT>             */<a name="line.152"></a>
<FONT color="green">153</FONT>            public Response getResponse(Stack path) {<a name="line.153"></a>
<FONT color="green">154</FONT>                    int i;<a name="line.154"></a>
<FONT color="green">155</FONT>                    Topic tmptopic;<a name="line.155"></a>
<FONT color="green">156</FONT>                    String topicname;<a name="line.156"></a>
<FONT color="green">157</FONT>    <a name="line.157"></a>
<FONT color="green">158</FONT>                    visited = true;<a name="line.158"></a>
<FONT color="green">159</FONT>    <a name="line.159"></a>
<FONT color="green">160</FONT>                    //Search each topic for a matching name in the path stack<a name="line.160"></a>
<FONT color="green">161</FONT>                    for (i = 0; i &lt; topics.size(); i++) {<a name="line.161"></a>
<FONT color="green">162</FONT>                            tmptopic = (Topic) topics.elementAt(i);<a name="line.162"></a>
<FONT color="green">163</FONT>                            topicname = tmptopic.getName();<a name="line.163"></a>
<FONT color="green">164</FONT>    <a name="line.164"></a>
<FONT color="green">165</FONT>                            //If found then process the subtopic<a name="line.165"></a>
<FONT color="green">166</FONT>                            if (topicname.equalsIgnoreCase((String) (path.peek()))) {<a name="line.166"></a>
<FONT color="green">167</FONT>                                    path.pop();<a name="line.167"></a>
<FONT color="green">168</FONT>                                    return (tmptopic.getResponse(path));<a name="line.168"></a>
<FONT color="green">169</FONT>                            }<a name="line.169"></a>
<FONT color="green">170</FONT>                    }<a name="line.170"></a>
<FONT color="green">171</FONT>                    return (null);<a name="line.171"></a>
<FONT color="green">172</FONT>            }<a name="line.172"></a>
<FONT color="green">173</FONT>    <a name="line.173"></a>
<FONT color="green">174</FONT>    <a name="line.174"></a>
<FONT color="green">175</FONT>            /**<a name="line.175"></a>
<FONT color="green">176</FONT>             *  Gets a default response<a name="line.176"></a>
<FONT color="green">177</FONT>             *<a name="line.177"></a>
<FONT color="green">178</FONT>             *@return    A response string consisting of either an absolute path and<a name="line.178"></a>
<FONT color="green">179</FONT>             *      filename, or a textual response<a name="line.179"></a>
<FONT color="green">180</FONT>             */<a name="line.180"></a>
<FONT color="green">181</FONT>            public Response getDefaultResponse() {<a name="line.181"></a>
<FONT color="green">182</FONT>                    return (defaulttopic.getDefaultResponse());<a name="line.182"></a>
<FONT color="green">183</FONT>            }<a name="line.183"></a>
<FONT color="green">184</FONT>    }<a name="line.184"></a>




























































</PRE>
</BODY>
</HTML>
